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Novel Supercritical Biodiesel Plant Design & Process Scale-Up, Ghana Shyam Paudel

Doctoral Dissertations

"Current energy prices, national energy security, and global climate change fuel our momentum to find efficient advanced fuels choices. In this study, biodiesel processing, and a novel design for next generation biodiesel plants are explored. During a National Science Foundation (NSF) I-Corps project we identified three creative and profitable improvements to the process: 1. Incorporating Energy intensive separations and reactions 2. Utilizing Low commodity glycerol and 3. Applying process intensification principles.

Current biodiesel processes are catalyzed processes using continuous stir reactors with distillation systems to separate material constituents. We tested a lab-scale nocatalyst supercritical biodiesel process using waste cooking oil …

Immobilized Lipase On Zif For Enhanced Biofuel Production, Reem Mohammed Al Mansouri

Theses

Enzymatic transesterification of triglycerides to produce biodiesel has been gaining increasing attention owing to its advantages over chemical processes. Being catalysts, enzymes are not consumed during the processes in which they are used. Therefore, a successful technique to allow their repeated use can significantly enhance the economic feasibility of the process. The most common approach to allow easy separation of the enzymes and to eliminate their wastage is immobilization on a support matrix. Recently, Metal-Organic Frameworks (MOFs) have been suggested as preferable support for enzyme immobilization, owing to their high-order structure and high porosity and specific surface area. This thesis …

Growth Of Microalgae For Simultaneous Treatment Of Industrial Wastewater And Biodiesel Production, Mohammed Ahmad Abujayya

Chemical and Petroleum Engineering Theses

The treatment of industrial wastewater contaminated with phenols is among the main challenges in the chemical, and particularly the petrochemical industry. Phenols, which present in considerable amounts in industrial wastewater, are toxic even at low concentrations. Therefore, it is essential to reduce their concentrations in water to harmless levels before being discharged. On the other hand, the dependence on the conventional fossil sources of energy, which is non-renewable, is not sustainable and can cause harmful environmental impacts. Therefore, in this work, the dual utilization of microalgae as a cheap and efficient means to remove phenolic compounds commonly found in refinery …

Using Switchable Solvents For Simultaneous Microalgae Lipids’ Extraction And Biodiesel Production, Mariam Sultan Saeed Alamer

Chemical and Petroleum Engineering Theses

Biodiesel produced from microalgae biomass has been pursued as a possible replacement to petroleum diesel. Among the main steps in microalgae biodiesel production are the drying and cell walls disruption, which are energy intensive and/or time consuming, and oil extraction, which is conventionally done using toxic organic solvents that contaminate the left over biomass and require additional solvent recovery. Therefore, these steps are considered the major obstacles facing the commercialization of microalgae biodiesel.

In this work, switchable solvents (SSs), which can reversibly alter their hydrophobicities, have been tested for oil extraction and biodiesel production. Three switchable solvents, namely N, N-dimethylcyclohexylamine …

Determination Of Growth Kinetics, Yield Coefficients And Biodiesel Properties For The Green Microalgae Scenedesmus Dimorphus In Freshwater And Saline Medias, Morgan L. Cohara

ETD Archive

Of the many alternative resources capable of generating biofuel, microalgal oil serves as a promising feedstock. Unfortunately, biodiesel production from microalgae is currently hindered by high operational costs. One primary causes for these high costs is the large quantity of freshwater required for cultivation. This experiment was designed to assess the feasibility of growing the green, freshwater microalgae Scenedesmus dimorphus in an increasingly saline environment. Both average yield coefficients and growth rates were monitored with increasing salt concentration. Determination of average yield coefficients allows for process scale-up and the optimization of production costs by minimizing raw material waste. Salinity was …

Evaluating One-Step Catalytic Free Method Including Hydrolysis, Esterification, Transesterification, And Degradation Reactions To Produce Biodiesel From Soybean Oil, Mahmood Gheni Jebur

Graduate Theses and Dissertations

Due to the environmental and economic impacts of diesel fuel based on petroleum, several studies have been done to find an alternative source of energy. Biodiesel is considered one of these alternative sources. It is a renewable source of energy produced from vegetable oils and animal fats. There are two main reaction routes used to produce biodiesel (fatty acid methyl esters). Transesterification reaction is the first route used to convert triglycerides to fatty acid methyl esters (FAMEs), while hydrolysis followed by esterification reactions are the second route employed to convert triglycerides to free fatty acids (FFA) and then further converted …

Esterification Of Free Fatty Acid By Selected Homogeneous And Solid Acid Catalysts For Biodiesel Production, Mohamed Kaddour

Electronic Thesis and Dissertation Repository

Biodiesel, derived from plant oils and animal fats is an attractive alternative fuel to fossil-based diesel as it is biodegradable, non-toxic, renewable, and has a low emission profile. Industrial production of biodiesel faces major challenges including limited supply of raw material and high cost of feedstock, which accounts for 60-80% of total production cost. Economic feasibility for biodiesel can be improved by using inexpensive raw materials such as waste frying oils and non-edible oils. However, these low quality feedstocks contain significant amounts of free fatty acids (FFA) which reacts with a base to produce soap hindering product separation and reduce …

Direct Conversion Of Wet Microalgae And Oleaginous Yeast To Biodiesel Using Ionic Liquids, Valerie Orr

Electronic Thesis and Dissertation Repository

This thesis examined the development of an oleaginous yeast or microalgae based biorefinery process. First, improvements were made to the Nile Red assay, a high-throughput method for monitoring lipid accumulation in oleaginous organisms resulting in a significantly more reproducible and accurate assay. This assay was then used to optimize lipid production during heterotrophic cultivation of microalgae on glucose using response surface methodology resulting in microalgae with high lipid content (37.6% wt.). In order to improve the renewability of heterotrophic lipid production, both oleaginous yeast and microalgae were cultivated using pyrolytic sugars, produced via fast pyrolysis of pinewood waste. The effects …

Stress Corrosion Cracking Evaluation Of Carbon Steel In Biodiesel And The Effect Of Ultrasonic Nanocrystal Surface Modification (Unsm) On 304 Stainless Steel, Josh Geyer

Williams Honors College, Honors Research Projects

The project that was performed was stress corrosion cracking (SSC) of carbon steel in biodiesel, petroleum diesel and a mixture. The project also included the effect of Ultrasonic Nanocrystal Surface Modification (UNSM) on 304 stainless steel. It included the assembly of a slow strain rate (SSR) machine and carrying out testing using the SSR machine. The assembly of the machine will require purchasing and building a stand to house the electrical equipment which includes the computer, actuator control panel and the actuator power supply. The assembly will also include designing and purchasing the connections to connect the actuator to the …

A Comprehensive Study Of Esterification Of Free Fatty Acid To Biodiesel In A Simulated Moving Bed System, Nillohit Mitra Ray

Electronic Thesis and Dissertation Repository

Simulated Moving Bed (SMB) systems are used for separations that are difficult using traditional separation techniques. Due to the advantage of adsorption-based chromatographic separation, SMB has shown promising application in petrochemical and sugar industries, and of late, for chiral drug separations. In recent years, the concept of integration of reaction and in-situ separation in a single unit has achieved considerable attention. The simulated moving bed reactor (SMBR) couples both these unit operations bringing down the operation costs while improving the process performance, particularly for products that require mild operating conditions. However, its application has been limited due to complexity of …

Improved Oxidative Stability In Biodiesel Via Commercially-Viable Processing Strategies, Gregory Lepak

All Theses

Biodiesel made from waste cooking oil (WCO) frequently requires antioxidants to meet oxidation stability specifications set forth in ASTM D6751 or EN 14214. In contrast, unrefined cottonseed oil (CSO), containing tocopherols and high concentrations of gossypol, a toxic polyphenolic antioxidant, is unique for biodiesel processing because it produces biodiesel resulting in higher oxidation stability. During biodiesel production, however, only a portion of these endogenous natural antioxidants are suspected to be retained. Because the economics of biodiesel manufacturing rely upon inexpensive sources of triglycerides, emphasis was placed upon developing improved alternative commercially-viable processing strategies where WCO is the main source of …

Phenol Deoxygenation Over Hydrotreating Catalysts, Madelyn R B Ball

Honors Theses and Capstones

Phenol deoxygenation has been investigated as a model reaction for the deoxygenation of fatty acid methyl esters in biodiesel. Hydrodeoxygenated biodiesel is a drop-in fuel for petroleum diesel, and is a premium diesel with a high cetane number. As the first step in this research, two molybdenum catalysts were prepared, characterized and tested in a small-scale reactor. These catalysts were found to produce small amounts of benzene and cyclohexanol in the product stream, and confirmed the activity of the catalyst. A commercial cobalt molybdenum catalyst (Harshaw HT-400) was also tested and benzene, cyclohexanol, and cyclohexane were identified as products. Future …

Investigations Of Cost-Effective Biodiesel Production From High Ffa Feedstock, Lesly N. Lesmes Sanchez

Electronic Thesis and Dissertation Repository

Commercial production of biodiesel from refined vegetable oils has been widely practiced. However, more economic raw materials are required in order to make biodiesel competitive in the fuel market. This is a challenge since low-cost lipid feedstock contains high concentrations of free fatty acids (FFA) and water, which inhibit transesterification. This work investigates new catalyst combinations and method configuration to develop a cost-effective and suitable process utilizing refined canola oil and canola oil with high oleic acid content. Results suggest that potassium carbonate is more tolerant to water in the feed and enhances phase separation when compared to traditional catalyst, …

Effects Of Biodiesel Concentration On Microbial Deterioration Of Polyethylene In A Simulated Fuel Storage Tank, Juan Manuel Restrepo-Florez

Electronic Thesis and Dissertation Repository

In this study a simulated fuel storage tank was used to investigate the effect of biodiesel concentration on biodegradation of polyethylene. This research is relevant in the field of fuel storage. The simulated storage system consisted of a number of identical conical flasks. Each flask was comprised of two layers, an upper one consisting of a fuel blend of diesel with biodiesel in concentrations ranging from 0 to 100% of biodiesel and the bottom layer containing an aqueous mineral media inoculated with a community obtained from a real fuel storage facility. Polyethylene slabs cut to a specific size were immersed …

Optimisation Of The Transesterification Stage Of Biodiesel Production Using Statistical Methods, Arnold Paintsil

Electronic Thesis and Dissertation Repository

The present research examines solely the transesterification stage of the biodiesel production process. Six process variables that affect the yield of biodiesel at this stage are examined using the 12 run Plackett-Burman Design. To study the effect of FFA[1] and to replicate real life situations where oil (feedstock) contain varying amounts of FFA, linoleic acid is used as FFA and intentionally added to high oleic acid canola oil containing less than 0.07% FFA. The process is catalyzed with potassium carbonate and evaluated at varying temperatures, stirring rates, reaction times and methanol oil ratios. The yields at the end of …

Application Of Synthetic Biology For Increasing Anaerobic Biodiesel Production In Escherichia Coli, Michael Christopher Wierzbicki

Masters Theses

The ever-increasing demand for transportation biofuels requires new and novel approaches to solve the complexities associated with efficient biofuel production. Ethanol, the most common biofuel, has physical limitation associated with difficulty of separations and issues with water contamination and as such is not a long-term transportation fuel solution. (Lou & Singh, 2010; Wheals, Basso, Alves, & Amorim, 1999) Biodiesel is seen as a possible alternative to ethanol due to its hydrophobicity and also has comparable energy density and cetane number to its petroleum derived counterpart. (Kalscheuer, Stölting, & Steinbüchel, 2006) Because of feedstock limitations, biodiesel produced from vegetable oils is …

The Impact Of Biodiesel-Based Na On The Durability Of Cu-Zeolite Scr Catalysts And Other Diesel Aftertreatment Devices, Daniel William Brookshear

Doctoral Dissertations

Biodiesel fuel has increased in popularity in recent years as an alternative fuel choice, but there are concerns related to the impact it will have on diesel engines and aftertreatment systems relative to conventional diesel fuel. One major concern is the presence of sodium (Na) in finished biodiesel fuel due to the use of Na-hydroxyl as a liquid-phase catalyst during biodiesel synthesis. The current study focuses on determining the impact of biodiesel-based Na on the performance and materials characterization of diesel aftertreatment devices including lean NOx traps (LNT), diesel oxidation catalysts (DOC), diesel particulate filters (DPF), and Cu-zeolite selective catalytic …

Kinetics Of Lipid Extraction From Microalgae, Brian Mcconnell

Honors Theses and Capstones

No abstract provided.

Liquid-Liquid Equilibrium Of Biodiesel Components, Joseph C. Bell

Theses and Dissertations

Biodiesel is produced from vegetable oils through transesterification. Triglyceride mixtures extracted from oilseed feedstocks are upgraded by reaction with an alcohol in the presence of a catalyst to produce fatty acid esters. This reaction produces a mixture of esters, glycerin, alcohol, and catalyst. Separation of the fatty acid esters (biodiesel) and glycerin can be accomplished through liquid-liquid extraction by water addition. Designing liquid-liquid extraction with water as the solvent requires ternary liquid-liquid equilibrium data for mixtures of water, glycerin, and fatty acid esters. Ternary mixture LLE data have been experimentally measured for several of these systems. Those measured include mixtures …

An Experimental Study On Thermal Stability Of Biodiesel Fuel, Yiying Zhu

Biomedical and Chemical Engineering – Theses

Biodiesel fuel, as renewable energy, has been used in conventional diesel engines in pure form or as biodiesel/diesel blends for many years. However, thermal stability of biodiesel and biodiesel/diesel blends has been minimally explored. Aimed to shorten this gap, thermal stability of biodiesel is investigated at high temperatures.

In this study, batch thermal stressing experiments of biodiesel fuel were performed in stainless steel coils at specific temperature and residence time range from 250 to 425 °C and 3 to 63 minutes, respectively.

Evidence of different pathways of biodiesel fuel degradation is demonstrated chromatographically. It was found that biodiesel was stable …

Investigations Of Transesterification Of Canola Oil With Methanol And Ethanol For A New Efficient Method Of Biodiesel Production, Krupal Pal

Electronic Thesis and Dissertation Repository

Transesterification of vegetable oil to biodiesel is a multistep process affected by mass transfer, mixing and chemical reaction equilibrium. Attempts have been made in this study to overcome these limitations by gradually feeding oil into a pool of alcohol. This approach provided large excess of alcohol to allow reaction to proceed further as well as allowed easy dispersion of oil into the alcohol. As a result improved conversion of feed, higher yield and better product quality were achieved. Comparisons have been made with other methods to show the differences and highlight improvements. Reactions were conducted at various reaction conditions for …

Transesterification And Recovery Of Intracellular Lipids Using A Single Step Reactive Extraction, Daniel R. Nelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A single-step, extractive reaction for extraction of lipids such as biodiesel components, omega-3 fatty acids, or other triglycerides from microbial cells was examined. Conventional methods for lipid extraction use toxic solvents, and require multiple steps and long processing times. When the goal is to produce fatty acid methyl esters or FAMEs, the extracted lipids are subjected to a separate transesterification reaction with simple alcohols in the presence of an acid or base catalyst. A simplified, single-step reactive extraction method can be applied that combines the sequential extraction followed by transesterification using acidified alcohols - a process known as in situ …

Nutrient Utilization From Anaerobic Digester Effluent Through Algae Cultivation, Shantanu Wahal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nutrients present in digested animal waste can be utilized for algae cultivation under suitable conditions. Algal growth, however, depends on the chemical forms and speciation of these nutrients. In this study a chemical equilibrium model was first used to describe nutrient speciation and predict conditions that enhance the solubility of nutrients in anaerobic digester effluent. Dilution with water and separation of large particulates greatly improved nutrient availability and light penetration - conditions favorable for algal cultivation. Algae growth was tested using three strains - Scenedesmus dimorphous (UTEX # 417), Chlorella vulgaris (UTEX# 265), and an algal isolate (designated as LLAI …

Temperature Influence And Heat Management Requirements Of Microalgae Cultivation In Photobioreactors, Thomas Hagen Mehlitz

Master's Theses

Microalgae are considered one of the most promising feedstocks for biofuel production for the future. The most efficient way to produce vast amounts of algal biomass is the use of closed tubular photobioreactors (PBR). The heat requirement for a given system is a major concern since the best algae growth rates are obtained between 25-30 °C, depending on the specific strain. A procedure to determine temperature influence on algal growth rates was developed for a lab-scale PBR system using the species Chlorella. A maximum growth rate of 1.44 doublings per day at 29 °C (optimal temperature) was determined. In addition, …

Kinetics Determination Of Soybean Oil Transesterification In The Design Of A Continuous Biodiesel Production Process, Irwin Jacob, Ed Clausen, Danielle Julie Carrier

Biological and Agricultural Engineering Undergraduate Honors Theses

One-step batch transesterification consisting of three stepwise reversible reactions of pure soybean oil with methanol was conducted at two different mixing speeds (600 and 300 rpm) to produce soybean oil fatty acid methyl esters (biodiesel). In both batch reactions, sodium methoxide (1.09 wt% based on soybean oil) was used as the catalyst, the reaction temperature was 60oC, and the methanol-to-oil molar ratio was 6:1. The objectives were to determine and/or investigate: 1) the mechanism and order of the reaction, 2) the reaction rate constants, 3) the effect of changes in mixing intensity on the reaction rate, 4) the comparison of …

Biodiesel Forming Reactions Using Heterogneous Catalysis, Yijun Liu

All Dissertations

Biodiesel synthesis from biomass provides a means for utilizing effectively renewable resources, a way to convert waste vegetable oils and animal fats to a useful product, a way to recycle carbon dioxide for a combustion fuel, and production of a fuel that is biodegradable, non-toxic, and has a lower emission profile than petroleum-diesel. Free fatty acid (FFA) esterification and triglyceride (TG) transesterification with low molecular weight alcohols constitute the synthetic routes to prepare biodiesel from lipid feedstocks. This project was aimed at developing a better understanding of important fundamental issues involved in heterogeneous catalyzed biodiesel forming reactions using mainly model …

Heterogeneous Catalysis And Biodiesel Forming Reactions, Dora Lopez

All Dissertations

Biodiesel, defined as 'a fuel comprised of mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats', is finding favor commercially worldwide. The objective of this study is to evaluate the use of solid catalysts for triglyceride transesterification and carboxylic acid esterification to produce biodiesel fuel.
Processes using mainly homogeneous alkali catalysts (such as NaOH, KOH, and methoxides) have been shown to be effective for biodiesel synthesis when dealing with virgin oil feedstocks. Use of acid catalysts (e.g., H2SO4) becomes important when processing low quality feedstocks that contain appreciable amounts of free fatty acids, such as …